An open-source car is like playing with building blocks, but on a much larger scale. A car is made up of many different parts, like the wheels, the engine and the seats. Now imagine if a bunch of people got together and decided that they wanted to build a car, but they wanted to share all of the instructions on how to build it with anyone who wanted to know. This means that you could learn how to build a car yourself, or you could add your own improvements to the design and share those with others too. It's like a big group project that everyone can take part in! By sharing all of the information about how the car is built, people can work together to make improvements and make the car better for everyone. And since it's open-source, no one person owns the design, so anyone can make their own version of the car without having to pay any money to a company. It's all about working together and sharing knowledge to make things better for everyone!